Conversion of sugars to ionic liquids

Patent metadata

Field	Value
Publication number	US-2019136281-A1
Application number	US-201716308440-A
Country	US
Kind code	A1
Filing date	Jun 7, 2017
Priority date	Jun 7, 2016
Publication date	May 9, 2019
Grant date	—

Abstract

Disclosed herein are methods for preparing sugar compositions. The methods include: i) forming a mixture including polysaccharide biomass and an ionic liquid solution, wherein the ionic liquid solution contains water and an ionic liquid, and the ionic liquid contains a) a cation and b) a sugar acid anion or a ketoacid anion; ii) maintaining the mixture under conditions sufficient to dissolve at least a portion of the polysaccharide present in the polysaccharide biomass; iii) adding at least one glycoside hydrolase to the mixture; and iv) maintaining the mixture containing the glycoside hydrolase under conditions sufficient to hydrolyze at least a portion of the dissolved polysaccharide, thereby forming the sugar compositions. The sugar compositions contain at least one monosaccharide or oligosaccharide. New sugar-based ionic liquids are also described.

First claim

1 . A method for preparing a sugar composition, the method comprising:
i) forming a mixture comprising polysaccharide biomass and an ionic liquid solution, wherein
the ionic liquid solution comprises water and an ionic liquid, and
the ionic liquid comprises a) a cation and b) a sugar acid anion or a ketoacid anion;
ii) maintaining the mixture under conditions sufficient to dissolve at least a portion of the polysaccharide present in the polysaccharide biomass; iii) adding at least one glycoside hydrolase to the mixture; and iv) maintaining the mixture containing the glycoside hydrolase under conditions sufficient to hydrolyze at least a portion of the dissolved polysaccharide, thereby forming the sugar composition; wherein the sugar composition comprises at least one monosaccharide or oligosaccharide.

2 . The method of claim 1 , wherein the sugar acid is selected from the group consisting of an aldaric acid, an aldonic acid, a uronic acid, and combinations thereof.

3 . The method of claim 1 , wherein the sugar acid is selected from the group consisting of mucic acid, saccharic acid, xylaric acid, arabinaric acid, and mannaric acid.

4 . The method of claim 1 , wherein the ketoacid is selected from the group consisting of α-ketoglutaric acid, pyruvic acid, and levulinic acid.

5 . The method of claim 1 , wherein the anion is selected from the group consisting of a mucic acid anion, a mucic acid dianion, an α-ketoglutaric acid anion, and an α-ketoglutaric acid dianion.

6 . The method of claim 1 , wherein the cation is selected from choline, (C 1-18 alkyl) 3 NH + , (C 1-6 alkyl) x (C 6-18 alkyl) y N + , (C 1-10 alkyl) z imidazol-ium, (C 1-10 alkyl) z pyrazolium, and mixtures thereof; wherein subscript x and subscript y are each 0, 1, 2, 3, or 4, and the sum of x and y is 4; and wherein each subscript z is 1, 2, or 3.

7 - 8 . (canceled)

9 . The method of claim 1 , wherein the ionic liquid solution comprises from about 25% (w/w) to about 95% (w/w) water.

10 . (canceled)

11 . The method of claim 1 , wherein the mixture in step i) comprises from about 5% (w/w) to about 30% (w/w) polysaccharide biomass.

12 . The method of claim 1 , wherein step ii) comprises maintaining the mixture of step i) at a temperature of at least about 100° C. for at least about 30 minutes.

13 . The method of claim 1 , wherein the pH of the mixture in step i) is greater than 7.

14 . The method of claim 13 , further comprising:
ii-b) reducing the pH of the mixture containing the dissolved polysaccharide to less than 7 prior to adding the glycoside hydrolase in step iii).

15 . The method of claim 14 , wherein step ii-b) comprises adding an acid to the mixture resulting from step ii).

16 . The method of claim 15 , wherein the acid used in step ii-b) is the same sugar acid or ketoacid used in step i).

17 - 18 . (canceled)

19 . The method of claim 1 , wherein the polysaccharide biomass comprises cellulose, hemicellulose, lignocellulose, or mixtures thereof.

20 - 21 . (canceled)

22 . The method claim 1 , wherein the glycoside hydrolase is a cellulase, an endoglucanase, an exoglucanase, a β-glucosidase, a xylanase, or a mixture thereof.

23 . (canceled)

24 . An ionic liquid comprising at least one anion and at least one cation, wherein the anion is selected from the group consisting of a sugar acid anion and a ketoacid ion.

25 . The ionic liquid of claim 24 , wherein the sugar acid is selected from the group consisting of an aldaric acid, an aldonic acid, a uronic acid, or a combination thereof.

26 . The ionic liquid of claim 24 , wherein the sugar acid is selected from the group consisting of mucic acid, saccharic acid, xylaric acid, arabinaric acid, and mannaric acid.

27 . The ionic liquid of claim 24 , wherein the ketoacid is selected from the group consisting of α-ketoglutaric acid, pyruvic acid, and levulinic acid.

28 . (canceled)

29 . The ionic liquid of claim 24 , wherein the cation is selected from choline, (C 1-18 alkyl) 3 NH + , (C 1-6 alkyl) x (C 6-18 alkyl) y N + , (C 1-10 alkyl) z imidazolium, (C 1-10 alkyl) z pyrazolium, and mixtures thereof; wherein subscript x and subscript y are each 0, 1, 2, 3, or 4, and the sum of x and y is 4; and wherein each subscript z is 1, 2, or 3.

30 . (canceled)

Assignees

• Nat Tech & Eng Solutions Sandia Llc

Inventors

• Gladden John M
• Dutta Tanmoy
• Sun Jian
• Singh Seema
• Simmons Blake A

Classifications

• C12P19/02

  Monosaccharides (2-ketogulonic acid C12P7/60) · CPC title

• C12Y302/01032

  Xylan endo-1,3-beta-xylosidase (3.2.1.32), i.e. endo-1-3-beta-xylanase · CPC title

• C07H1/00

  Processes for the preparation of sugar derivatives · CPC title

• C12Y302/01021

  Beta-glucosidase (3.2.1.21) · CPC title

• C07H3/02

  Monosaccharides · CPC title